Answer:
It's important to know that if the ratio is 19:1, it means there are 20 total parts, where 19 represents students and 1 represents teachers.
Now, let's solve for each number of people.
- For 100 people, there are 100/20 total parts, which are 5. This means there are 5 teachers to 95 students.
- For 280 people, there are 280/20 total parts, which are 14. This means there are 14 teachers to 266 students.
- For 440 people, there are 440/20 total parts, which are 22. This means there are 22 teachers to 418 students.
- For 760 people, there are 760/20 total parts, which are 38. This means there are 38 teachers to 722 students.
So, to solve problems like this with ratios, you just need to know how many total parts there are, then you divide the total number of people by the total number of parts, that will give you the number of teachers, then you subtract to find the number of students.